SMR exhaust mod

Ok, let's see what sort of pain we can inflict upon the stock exhaust can! I wanted to shorten the can a little bit as well as remove the restrictive inner silencing core, to make it look and sound a bit better. Here is what you find after drilling out the rivets and pulling off the end-cap.

 

I measured and marked points around the can to mark the distance I wanted to remove. The 1st line you see was my first thought (2") but I decided to add a bit more (3/8"). Holding the strap along the marks to use as a guide, I marked the final cut line. I would have cut a bit more off the can, but I liked the idea of leaving the existing stamp that states the exhaust meets emission and sound requirements :)

 

Being lazy and not wanting to leave home, I cut the exhaust by hand using a hacksaw. There are many other, better ways to make this cut but this was all I had at home. After cutting off the end of the can and trimming back the packing material (leaving a little sticking out to fill the end-cap), you see the inner screen. The screen is tapered a bit so that it slips inside the larger tube in the endcap. I wanted to keep some overlap with the modified setup, so using a Dremel I cut the screen down to about 1/2" inside the edge of the outside can (how it was at the original length).

 

I figured the easiest way to get overlap again was to make some cuts and flare it out, so that it will slide over the large tube on the end cap. I am putting it on the outside of the large tube since I will be removing the smaller inner tube.

 

The next step was to cut out the inner tube, again using a Dremel with a cut-off wheel. To avoid cutting the area where the larger tube is welded to the end cap, I cut a bit further inward than I needed to. Now I can go back and grind off the excess part of the remaining inner tube.

 

The inner tube is connected all the way out at the outer weld, so I carefully cut off as much as I could, then filed the remaining seam out. What I ended up with is a smooth surface all the way through the remaining tube.

 

Using the existing holes in the endcap as well as the strap as guides, I marked where I needed to drill holes at the end of the exhaust can. The last step was to rivet it all back together.

 

Here it is back on the bike, the 3rd picture being an old one for reference.

 

Lastly, the video.